2600 jnr colour problem

[LU8]

Hello, I am having some problems with my PAL 2600 jnr. It seems to display the games brighter than they should be. When I play the same 2600 game carts in my PAL 7800 the games appear at the correct level of brightness.

Often this odd quality makes the 2600 games played on my 2600 jnr seem nicer, the graphics are more vibrant, it looks more attractive. Examples of this would be Pac Man and Jnr. Pac Man. However, on some games there is a slight streaking effect e.g. title screen to Crystal Castles where the white words against the blue background streak slightly.

The bad side to this occurs in games with beige or cream borders, strips or surrounds. On Frogger the strip where the Frog starts out from, and the centre strip where the snake walks, has become so bright that the frog and the snake can't be seen. But the game plays normally when you switch to black & white mode. The same problem occurs with the 1989 game Secret Quest, the beige/ sand coloured border appears strange. Plus there is a background interference noise that obscures the game's normal sound.

Any ideas on what's wrong with my 2600 jnr? BTW with Frogger the game appeared better once I turned the colour down, the playfield bent back into shape, but the problem with the snake walkway being obscured remains.

As it stands I have to play some 2600 games on my 7800 so that they appear normal.